package com.financing.util;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Formatter;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;

import com.alibaba.fastjson.JSONObject;  

public class WechatSign {

	public static void main(String[] args) throws Exception {
        String res = Http.post("https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=wxd00d9d5b47fb1005&secret=d85aac74a36703bd9710a444d8be0726");

        System.out.println(res);
        String accessToken = JSONObject.parseObject(res).getString("access_token");
        res = Http.post("https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token="+accessToken+"&type=jsapi");
        String jsapi = JSONObject.parseObject(res).getString("ticket");
        Map<String, String> ret = WechatSign.sign(jsapi, "https://www.ymbcai.com/app/page/user-friendsInvite");
        for (Map.Entry entry : ret.entrySet()) {
            System.out.println(entry.getKey() + ", " + entry.getValue());
        }
	}
	
    public static Map<String, String> sign(String jsapi_ticket, String url) {
        Map<String, String> ret = new HashMap<String, String>();
        String nonce_str = create_nonce_str();
        String timestamp = create_timestamp();
        String string1;
        String signature = "";

        //注意这里参数名必须全部小写，且必须有序
        string1 = "jsapi_ticket=" + jsapi_ticket +
                  "&noncestr=" + nonce_str +
                  "&timestamp=" + timestamp +
                  "&url=" + url;

        try
        {
            MessageDigest crypt = MessageDigest.getInstance("SHA-1");
            crypt.reset();
            crypt.update(string1.getBytes("UTF-8"));
            signature = byteToHex(crypt.digest());
        }
        catch (NoSuchAlgorithmException e)
        {
            e.printStackTrace();
        }
        catch (UnsupportedEncodingException e)
        {
            e.printStackTrace();
        }

        ret.put("url", url);
        ret.put("jsapi_ticket", jsapi_ticket);
        ret.put("nonceStr", nonce_str);
        ret.put("timestamp", timestamp);
        ret.put("signature", signature);

        return ret;
    }

    private static String byteToHex(final byte[] hash) {
        Formatter formatter = new Formatter();
        for (byte b : hash)
        {
            formatter.format("%02x", b);
        }
        String result = formatter.toString();
        formatter.close();
        return result;
    }

    private static String create_nonce_str() {
        return UUID.randomUUID().toString();
    }

    private static String create_timestamp() {
        return Long.toString(System.currentTimeMillis() / 1000);
    }
}
